Channel Distribution and Noise Characteristics of Distributed Acoustic Sensing Underwater Communications
Channel Distribution and Noise Characteristics of Distributed Acoustic Sensing Underwater Communications
复制标题
分布式声传感水下通信的信道分布和噪声特性
DOI：
10.1109/jsen.2021.3115581
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发表时间：
2021-11
影响因子：
4.3
通讯作者：
Fengzhong Qu
中科院分区：
文献类型：
--
作者：
Mingjiu Zuo;Xingbin Tu;Shaojian Yang;Hao Fang;Xin Wen;Xin Wen;Fengzhong Qu
由于功率和传输速率的限制，实现从无人水下航行器（UUV）到岸站的长距离水声（UWA）通信具有挑战性。作为替代解决方案，分布式声学传感（DAS）水下通信使用海底光缆来获取和解调声学通信信号。关于DAS水下通信的信道和噪声的研究很少。本文通过实验测量分析了铠装光缆DAS水下通信系统的信道特性和背景噪声。通道分析表明脉冲响应的包络幅度遵循 Burr 分布。当声源靠近光缆正上方的位置时，振幅会集中在较低的值上。此外，我们观察到接收到的信号受到相邻段的影响，导致每个声学反弹内有多个到达。噪声分析表明，对于低于 1 kHz 的频率，与主要由船舶和风引起的 Wenz 噪声谱不同，DAS 噪声的功率谱密度 (PSD) -18 dB/倍频程下降主要是由设备和电缆本身引起的。噪声还表现出全频带波动。在水下通信中，全频带噪声给信号设计带来了重大挑战。据了解，本文是首篇采用配备铠装光缆的DAS水下通信系统进行现场实验的报告，为未来水下应用提供参考。
Due to the power and transmission rate limitations, it is challenging to achieve underwater acoustic (UWA) communications over long distances from the unmanned underwater vehicle (UUV) to the shore station. As an alternative solution, the distributed acoustic sensing (DAS) underwater communication uses submarine optical cable to acquire and demodulate acoustic communication signals. There is little research on the channel and noise of DAS underwater communication. This paper analyzes the channel characteristics and the background noise of a DAS underwater communication system with armored optical cable based on the experimental measurements. Channel analysis shows that the envelope amplitudes of impulse responses follow the Burr distribution. The amplitudes get increased concentration at lower values as the sound source goes closer to the position right above the optical cable. Moreover, we observe that the received signals are influenced by the adjacent segments, leading to multiple arrivals within each acoustic bounce. Noise analysis shows that for frequencies lower than 1 kHz, unlike the Wenz noise spectrum primarily caused by shipping and wind, the −18 dB/octave decrease in power spectral density (PSD) of DAS noise is mainly caused by the equipment and cable themselves. The noise also exhibits full-band fluctuations. In underwater communications, full-band noise poses significant challenges for signal design. As far as we know, this article is the first report on the field experiment using a DAS underwater communication system equipped with armored optical cable, providing a reference for future underwater applications.